Answer:
The sled needed a distance of 92.22 m and a time of 1.40 s to stop.
Explanation:
The relationship between velocities and time is described by this equation: 
, where 
is the final velocity, 
is the initial velocity, 
the acceleration, and 
is the time during such acceleration is applied.
Solving the equation for the time, and applying to the case: 
, where 
because the sled is totally stopped, 
is the velocity of the sled before braking and, 
is negative because the deceleration applied by the brakes.
In the other hand, the equation that describes the distance in term of velocities and acceleration:
, where 
is the distance traveled, is the initial velocity, the time of the process and, is the acceleration of the process.
Then for this case the relationship becomes: 
.
<u>Note that the acceleration is negative because is a braking process.</u>
Let 
be the height of the building and thus the initial height of the ball. The ball's altitude at time is given by
where 
is the acceleration due to gravity.
The ball reaches the ground when 
after 
. Solve for :
so the building is about 16 m tall (keeping track of significant digits).
Answer:
Work = 5941 J
Explanation:
As we know that work done is given by the equation
here we know that
also we have
now from above formula we have
Answer:
R = 98304.75 m = 98.3 km
Explanation:
The density of an object is given as the ratio between the mass of that object and the volume occupied by that object.
Density = Mass/Volume
Now, it is given that the density of Earth has become:
Density = 1 x 10⁹ kg/m³
Mass = Mass of Earth (Constant) = 5.97 x 10²⁴ kg
Volume = 4/3πR³ (Volume of Sphere)
R = Radius of Earth = ?
Therefore,
1 x 10⁹ kg/m³ = (5.97 x 10²⁴ kg)/[4/3πR³]
4/3πR³ = (5.97 x 10²⁴ kg)/(1 x 10⁹ kg/m³)
R³ = (3/4)(5.97 x 10¹⁵ m³)/π
R = ∛[0.95 x 10¹⁵ m³]
<u>R = 98304.75 m = 98.3 km</u>
The answer would be c because it is talking about she wants to be in a good neighborhood
